text: /*
   * This file is part of the MicroPython project, http://micropython.org/
   *
   * The MIT License (MIT)
   *
   * Copyright (c) 2013-2015 Damien P. George
   * Copyright (c) 2016 Paul Sokolovsky
   *
   * Permission is hereby granted, free of charge, to any person obtaining a copy
   * of this software and associated documentation files (the "Software"), to deal
   * in the Software without restriction, including without limitation the rights
   * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
   * copies of the Software, and to permit persons to whom the Software is
   * furnished to do so, subject to the following conditions:
   *
   * The above copyright notice and this permission notice shall be included in
   * all copies or substantial portions of the Software.
   *
   * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
   * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
   * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
   * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
   * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
   * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
   * THE SOFTWARE.
   */
  
  #include <stdint.h>
  #include <stdio.h>
  
  #include "py/obj.h"
  #include "py/runtime.h"
  
  // This needs to be set before we include the RTOS headers
  #define USE_US_TIMER 1
  
  #include "extmod/machine_mem.h"
  #include "extmod/machine_signal.h"
  #include "extmod/machine_pulse.h"
  #include "extmod/machine_i2c.h"
  #include "modmachine.h"
  
  #include "xtirq.h"
  #include "os_type.h"
  #include "osapi.h"
  #include "etshal.h"
  #include "ets_alt_task.h"
  #include "user_interface.h"
  
  #if MICROPY_PY_MACHINE
  
  //#define MACHINE_WAKE_IDLE (0x01)
  //#define MACHINE_WAKE_SLEEP (0x02)
  #define MACHINE_WAKE_DEEPSLEEP (0x04)
  
  extern const mp_obj_type_t esp_wdt_type;
  
  STATIC mp_obj_t machine_freq(size_t n_args, const mp_obj_t *args) {
      if (n_args == 0) {
          // get
          return mp_obj_new_int(system_get_cpu_freq() * 1000000);
      } else {
          // set
          mp_int_t freq = mp_obj_get_int(args[0]) / 1000000;
          if (freq != 80 && freq != 160) {
              mp_raise_ValueError("frequency can only be either 80Mhz or 160MHz");
          }
          system_update_cpu_freq(freq);
          return mp_const_none;
      }
  }
  STATIC MP_DEFINE_CONST_FUN_OBJ_VAR_BETWEEN(machine_freq_obj, 0, 1, machine_freq);
  
  STATIC mp_obj_t machine_reset(void) {
      system_restart();
      return mp_const_none;
  }
  STATIC MP_DEFINE_CONST_FUN_OBJ_0(machine_reset_obj, machine_reset);
  
  STATIC mp_obj_t machine_reset_cause(void) {
      return MP_OBJ_NEW_SMALL_INT(system_get_rst_info()->reason);
  }
  STATIC MP_DEFINE_CONST_FUN_OBJ_0(machine_reset_cause_obj, machine_reset_cause);
  
  STATIC mp_obj_t machine_unique_id(void) {
      uint32_t id = system_get_chip_id();
      return mp_obj_new_bytes((byte*)&id, sizeof(id));
  }
  STATIC MP_DEFINE_CONST_FUN_OBJ_0(machine_unique_id_obj, machine_unique_id);
  
  STATIC mp_obj_t machine_idle(void) {
      uint32_t t = mp_hal_ticks_cpu();
      asm("waiti 0");
      t = mp_hal_ticks_cpu() - t;
      ets_event_poll(); // handle any events after possibly a long wait (eg feed WDT)
      return MP_OBJ_NEW_SMALL_INT(t);
  }
  STATIC MP_DEFINE_CONST_FUN_OBJ_0(machine_idle_obj, machine_idle);
  
  STATIC mp_obj_t machine_lightsleep(size_t n_args, const mp_obj_t *args) {
      uint32_t max_us = 0xffffffff;
      if (n_args == 1) {
          mp_int_t max_ms = mp_obj_get_int(args[0]);
          if (max_ms < 0) {
              max_ms = 0;
          }
          max_us = max_ms * 1000;
      }
      uint32_t wifi_mode = wifi_get_opmode();
      uint32_t start = system_get_time();
      while (system_get_time() - start <= max_us) {
          ets_event_poll();
          if (wifi_mode == NULL_MODE) {
              // Can only idle if the wifi is off
              asm("waiti 0");
          }
      }
      return mp_const_none;
  }
  STATIC MP_DEFINE_CONST_FUN_OBJ_VAR_BETWEEN(machine_lightsleep_obj, 0, 1, machine_lightsleep);
  
  STATIC mp_obj_t machine_deepsleep(size_t n_args, const mp_obj_t *args) {
      // default to sleep forever
      uint32_t sleep_us = 0;
  
      // see if RTC.ALARM0 should wake the device
      if (pyb_rtc_alarm0_wake & MACHINE_WAKE_DEEPSLEEP) {
          uint64_t t = pyb_rtc_get_us_since_2000();
          if (pyb_rtc_alarm0_expiry <= t) {
              sleep_us = 1; // alarm already expired so wake immediately
          } else {
              uint64_t delta = pyb_rtc_alarm0_expiry - t;
              if (delta <= 0xffffffff) {
                  // sleep for the desired time
                  sleep_us = delta;
              } else {
                  // overflow, just set to maximum sleep time
                  sleep_us = 0xffffffff;
              }
          }
      }
  
      // if an argument is given then that's the maximum time to sleep for
      if (n_args == 1) {
          mp_int_t max_ms = mp_obj_get_int(args[0]);
          if (max_ms <= 0) {
              max_ms = 1;
          }
          uint32_t max_us = max_ms * 1000;
          if (sleep_us == 0 || max_us < sleep_us) {
              sleep_us = max_us;
          }
      }
  
      // prepare for RTC reset at wake up
      rtc_prepare_deepsleep(sleep_us);
      // put the device in a deep-sleep state
      system_deep_sleep_set_option(0); // default power down mode; TODO check this
      system_deep_sleep(sleep_us);
  
      for (;;) {
          // we must not return
          ets_loop_iter();
      }
  
      return mp_const_none;
  }
  STATIC MP_DEFINE_CONST_FUN_OBJ_VAR_BETWEEN(machine_deepsleep_obj, 0, 1, machine_deepsleep);
  
  // These values are from the datasheet
  #define ESP_TIMER_US_MIN (100)
  #define ESP_TIMER_US_MAX (0xfffffff)
  #define ESP_TIMER_MS_MAX (0x689d0)
  
  typedef struct _esp_timer_obj_t {
      mp_obj_base_t base;
      os_timer_t timer;
      uint32_t remain_ms; // if non-zero, remaining time to handle large periods
      uint32_t period_ms; // if non-zero, periodic timer with a large period
      mp_obj_t callback;
  } esp_timer_obj_t;
  
  STATIC void esp_timer_arm_ms(esp_timer_obj_t *self, uint32_t ms, bool repeat) {
      if (ms <= ESP_TIMER_MS_MAX) {
          self->remain_ms = 0;
          self->period_ms = 0;
      } else {
          self->remain_ms = ms - ESP_TIMER_MS_MAX;
          if (repeat) {
              repeat = false;
              self->period_ms = ms;
          } else {
              self->period_ms = 0;
          }
          ms = ESP_TIMER_MS_MAX;
      }
      os_timer_arm(&self->timer, ms, repeat);
  }
  
  STATIC void esp_timer_arm_us(esp_timer_obj_t *self, uint32_t us, bool repeat) {
      if (us < ESP_TIMER_US_MIN) {
          us = ESP_TIMER_US_MIN;
      }
      if (us <= ESP_TIMER_US_MAX) {
          self->remain_ms = 0;
          self->period_ms = 0;
          os_timer_arm_us(&self->timer, us, repeat);
      } else {
          esp_timer_arm_ms(self, us / 1000, repeat);
      }
  }
  
  const mp_obj_type_t esp_timer_type;
  
  STATIC void esp_timer_print(const mp_print_t *print, mp_obj_t self_in, mp_print_kind_t kind) {
      esp_timer_obj_t *self = self_in;
      mp_printf(print, "Timer(%p)", &self->timer);
  }
  
  STATIC mp_obj_t esp_timer_make_new(const mp_obj_type_t *type, size_t n_args, size_t n_kw, const mp_obj_t *args) {
      mp_arg_check_num(n_args, n_kw, 1, 1, false);
      esp_timer_obj_t *tim = m_new_obj(esp_timer_obj_t);
      tim->base.type = &esp_timer_type;
      return tim;
  }
  
  STATIC void esp_timer_cb(void *arg) {
      esp_timer_obj_t *self = arg;
      if (self->remain_ms != 0) {
          // Handle periods larger than the maximum system period
          uint32_t next_period_ms = self->remain_ms;
          if (next_period_ms > ESP_TIMER_MS_MAX) {
              next_period_ms = ESP_TIMER_MS_MAX;
          }
          self->remain_ms -= next_period_ms;
          os_timer_arm(&self->timer, next_period_ms, false);
      } else {
          mp_sched_schedule(self->callback, self);
          if (self->period_ms != 0) {
              // A periodic timer with a larger period: reschedule it
              esp_timer_arm_ms(self, self->period_ms, true);
          }
      }
  }
  
  STATIC mp_obj_t esp_timer_init_helper(esp_timer_obj_t *self, size_t n_args, const mp_obj_t *pos_args, mp_map_t *kw_args) {
      enum {
          ARG_mode,
          ARG_callback,
          ARG_period,
          ARG_tick_hz,
          ARG_freq,
      };
      static const mp_arg_t allowed_args[] = {
          { MP_QSTR_mode,         MP_ARG_KW_ONLY | MP_ARG_INT, {.u_int = 1} },
          { MP_QSTR_callback,     MP_ARG_KW_ONLY | MP_ARG_OBJ, {.u_obj = mp_const_none} },
          { MP_QSTR_period,       MP_ARG_KW_ONLY | MP_ARG_INT, {.u_int = 0xffffffff} },
          { MP_QSTR_tick_hz,      MP_ARG_KW_ONLY | MP_ARG_INT, {.u_int = 1000} },
  #if MICROPY_PY_BUILTINS_FLOAT
          { MP_QSTR_freq,         MP_ARG_KW_ONLY | MP_ARG_OBJ, {.u_obj = mp_const_none} },
  #else
          { MP_QSTR_freq,         MP_ARG_KW_ONLY | MP_ARG_INT, {.u_int = 0xffffffff} },
  #endif
      };
  
      // parse args
      mp_arg_val_t args[MP_ARRAY_SIZE(allowed_args)];
      mp_arg_parse_all(n_args, pos_args, kw_args, MP_ARRAY_SIZE(allowed_args), allowed_args, args);
  
      self->callback = args[ARG_callback].u_obj;
      // Be sure to disarm timer before making any changes
      os_timer_disarm(&self->timer);
      os_timer_setfn(&self->timer, esp_timer_cb, self);
  
  #if MICROPY_PY_BUILTINS_FLOAT
      if (args[ARG_freq].u_obj != mp_const_none) {
          mp_float_t freq = mp_obj_get_float(args[ARG_freq].u_obj);
          if (freq < 0.001) {
              esp_timer_arm_ms(self, (mp_int_t)(1000 / freq), args[ARG_mode].u_int);
          } else {
              esp_timer_arm_us(self, (mp_int_t)(1000000 / freq), args[ARG_mode].u_int);
          }
      }
  #else
      if (args[ARG_freq].u_int != 0xffffffff) {
          esp_timer_arm_us(self, 1000000 / args[ARG_freq].u_int, args[ARG_mode].u_int);
      }
  #endif
      else {
          mp_int_t period = args[ARG_period].u_int;
          mp_int_t hz = args[ARG_tick_hz].u_int;
          if (hz == 1000) {
              esp_timer_arm_ms(self, period, args[ARG_mode].u_int);
          } else if (hz == 1000000) {
              esp_timer_arm_us(self, period, args[ARG_mode].u_int);
          } else {
              // Use a long long to ensure that we don't either overflow or loose accuracy
              uint64_t period_us = (((uint64_t)period) * 1000000) / hz;
              if (period_us < 0x80000000ull) {
                  esp_timer_arm_us(self, (mp_int_t)period_us, args[ARG_mode].u_int);
              } else {
                  esp_timer_arm_ms(self, (mp_int_t)(period_us / 1000), args[ARG_mode].u_int);
              }
          }
      }
  
      return mp_const_none;
  }
  
  STATIC mp_obj_t esp_timer_init(size_t n_args, const mp_obj_t *args, mp_map_t *kw_args) {
      return esp_timer_init_helper(args[0], n_args - 1, args + 1, kw_args);
  }
  STATIC MP_DEFINE_CONST_FUN_OBJ_KW(esp_timer_init_obj, 1, esp_timer_init);
  
  STATIC mp_obj_t esp_timer_deinit(mp_obj_t self_in) {
      esp_timer_obj_t *self = self_in;
      os_timer_disarm(&self->timer);
      return mp_const_none;
  }
  STATIC MP_DEFINE_CONST_FUN_OBJ_1(esp_timer_deinit_obj, esp_timer_deinit);
  
  STATIC const mp_rom_map_elem_t esp_timer_locals_dict_table[] = {
      { MP_ROM_QSTR(MP_QSTR_deinit), MP_ROM_PTR(&esp_timer_deinit_obj) },
      { MP_ROM_QSTR(MP_QSTR_init), MP_ROM_PTR(&esp_timer_init_obj) },
  //    { MP_ROM_QSTR(MP_QSTR_callback), MP_ROM_PTR(&esp_timer_callback_obj) },
      { MP_ROM_QSTR(MP_QSTR_ONE_SHOT), MP_ROM_INT(false) },
      { MP_ROM_QSTR(MP_QSTR_PERIODIC), MP_ROM_INT(true) },
  };
  STATIC MP_DEFINE_CONST_DICT(esp_timer_locals_dict, esp_timer_locals_dict_table);
  
  const mp_obj_type_t esp_timer_type = {
      { &mp_type_type },
      .name = MP_QSTR_Timer,
      .print = esp_timer_print,
      .make_new = esp_timer_make_new,
      .locals_dict = (mp_obj_dict_t*)&esp_timer_locals_dict,
  };
  
  // this bit is unused in the Xtensa PS register
  #define ETS_LOOP_ITER_BIT (12)
  
  STATIC mp_obj_t machine_disable_irq(void) {
      uint32_t state = disable_irq();
      state = (state & ~(1 << ETS_LOOP_ITER_BIT)) | (ets_loop_iter_disable << ETS_LOOP_ITER_BIT);
      ets_loop_iter_disable = 1;
      return mp_obj_new_int(state);
  }
  MP_DEFINE_CONST_FUN_OBJ_0(machine_disable_irq_obj, machine_disable_irq);
  
  STATIC mp_obj_t machine_enable_irq(mp_obj_t state_in) {
      uint32_t state = mp_obj_get_int(state_in);
      ets_loop_iter_disable = (state >> ETS_LOOP_ITER_BIT) & 1;
      enable_irq(state & ~(1 << ETS_LOOP_ITER_BIT));
      return mp_const_none;
  }
  MP_DEFINE_CONST_FUN_OBJ_1(machine_enable_irq_obj, machine_enable_irq);
  
  // Custom version of this function that feeds system WDT if necessary
  mp_uint_t machine_time_pulse_us(mp_hal_pin_obj_t pin, int pulse_level, mp_uint_t timeout_us) {
      int nchanges = 2;
      uint32_t start = system_get_time(); // in microseconds
      for (;;) {
          uint32_t dt = system_get_time() - start;
  
          // Check if pin changed to wanted value
          if (mp_hal_pin_read(pin) == pulse_level) {
              if (--nchanges == 0) {
                  return dt;
              }
              pulse_level = 1 - pulse_level;
              start = system_get_time();
              continue;
          }
  
          // Check for timeout
          if (dt >= timeout_us) {
              return (mp_uint_t)-nchanges;
          }
  
          // Only feed WDT every now and then, to make sure edge timing is accurate
          if ((dt & 0xffff) == 0xffff && !ets_loop_dont_feed_sw_wdt) {
              system_soft_wdt_feed();
          }
      }
  }
  
  STATIC const mp_rom_map_elem_t machine_module_globals_table[] = {
      { MP_ROM_QSTR(MP_QSTR___name__), MP_ROM_QSTR(MP_QSTR_umachine) },
      { MP_ROM_QSTR(MP_QSTR_mem8), MP_ROM_PTR(&machine_mem8_obj) },
      { MP_ROM_QSTR(MP_QSTR_mem16), MP_ROM_PTR(&machine_mem16_obj) },
      { MP_ROM_QSTR(MP_QSTR_mem32), MP_ROM_PTR(&machine_mem32_obj) },
  
      { MP_ROM_QSTR(MP_QSTR_freq), MP_ROM_PTR(&machine_freq_obj) },
      { MP_ROM_QSTR(MP_QSTR_reset), MP_ROM_PTR(&machine_reset_obj) },
      { MP_ROM_QSTR(MP_QSTR_reset_cause), MP_ROM_PTR(&machine_reset_cause_obj) },
      { MP_ROM_QSTR(MP_QSTR_unique_id), MP_ROM_PTR(&machine_unique_id_obj) },
      { MP_ROM_QSTR(MP_QSTR_idle), MP_ROM_PTR(&machine_idle_obj) },
      { MP_ROM_QSTR(MP_QSTR_sleep), MP_ROM_PTR(&machine_lightsleep_obj) },
      { MP_ROM_QSTR(MP_QSTR_lightsleep), MP_ROM_PTR(&machine_lightsleep_obj) },
      { MP_ROM_QSTR(MP_QSTR_deepsleep), MP_ROM_PTR(&machine_deepsleep_obj) },
  
      { MP_ROM_QSTR(MP_QSTR_disable_irq), MP_ROM_PTR(&machine_disable_irq_obj) },
      { MP_ROM_QSTR(MP_QSTR_enable_irq), MP_ROM_PTR(&machine_enable_irq_obj) },
  
      { MP_ROM_QSTR(MP_QSTR_time_pulse_us), MP_ROM_PTR(&machine_time_pulse_us_obj) },
  
      { MP_ROM_QSTR(MP_QSTR_RTC), MP_ROM_PTR(&pyb_rtc_type) },
      { MP_ROM_QSTR(MP_QSTR_Timer), MP_ROM_PTR(&esp_timer_type) },
      { MP_ROM_QSTR(MP_QSTR_WDT), MP_ROM_PTR(&esp_wdt_type) },
      { MP_ROM_QSTR(MP_QSTR_Pin), MP_ROM_PTR(&pyb_pin_type) },
      { MP_ROM_QSTR(MP_QSTR_Signal), MP_ROM_PTR(&machine_signal_type) },
      { MP_ROM_QSTR(MP_QSTR_PWM), MP_ROM_PTR(&pyb_pwm_type) },
      { MP_ROM_QSTR(MP_QSTR_ADC), MP_ROM_PTR(&machine_adc_type) },
      { MP_ROM_QSTR(MP_QSTR_UART), MP_ROM_PTR(&pyb_uart_type) },
      #if MICROPY_PY_MACHINE_I2C
      { MP_ROM_QSTR(MP_QSTR_I2C), MP_ROM_PTR(&machine_i2c_type) },
      #endif
      #if MICROPY_PY_MACHINE_SPI
      { MP_ROM_QSTR(MP_QSTR_SPI), MP_ROM_PTR(&machine_hspi_type) },
      #endif
  
      // wake abilities
      { MP_ROM_QSTR(MP_QSTR_DEEPSLEEP), MP_ROM_INT(MACHINE_WAKE_DEEPSLEEP) },
  
      // reset causes
      { MP_ROM_QSTR(MP_QSTR_PWRON_RESET), MP_ROM_INT(REASON_DEFAULT_RST) },
      { MP_ROM_QSTR(MP_QSTR_HARD_RESET), MP_ROM_INT(REASON_EXT_SYS_RST) },
      { MP_ROM_QSTR(MP_QSTR_DEEPSLEEP_RESET), MP_ROM_INT(REASON_DEEP_SLEEP_AWAKE) },
      { MP_ROM_QSTR(MP_QSTR_WDT_RESET), MP_ROM_INT(REASON_WDT_RST) },
      { MP_ROM_QSTR(MP_QSTR_SOFT_RESET), MP_ROM_INT(REASON_SOFT_RESTART) },
  };
  
  STATIC MP_DEFINE_CONST_DICT(machine_module_globals, machine_module_globals_table);
  
  const mp_obj_module_t mp_module_machine = {
      .base = { &mp_type_module },
      .globals = (mp_obj_dict_t*)&machine_module_globals,
  };
  
  #endif // MICROPY_PY_MACHINE
  